Populating collections that subclass List<>

Hi,
I'm trying to populating a collection that subclasses of List<> and am running into a few hiccups. I'll reference the Northwind db throughout this example.

I'm trying to have a picture perfect object model and want to populate an "OrderCollection" rather than a List<Order>. I've only just started, but ran into an exception in BuildEntityExpression where Expression.Bind complains that "Argument
types do not match". I was hoping someone could point me in the right direction. Thanks!

You've defined OrderCollection as List<OrderDetail>. I assume this is a mistake. You'll also need to define a constructor that takes IEnumerable<Order> to get the query
translator to work with your custom collection type.